Gemini 3.1 Pro vs GPT-5.1
Wins 7 of 7 areas
Coding · Agents · Reasoning · Facts · Images and charts · Long documents · Following instructions
Wins 0 of 7 areas
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Gemini 3.1 Pro is the stronger all-rounder.GPT-5.1 is cheaper.
Scores updated · 39 tests both models report · How we compare
Where each one wins
Tests won in each of the seven areas where both have results. Each piece is one test, so a longer bar means more evidence; grey means the two scored within a point of each other.
- CodingWriting and fixing software60Gemini 3.1 Pro6 of 6 tests
- ReasoningHard problems that need careful thinking50Gemini 3.1 Pro5 of 5 tests
- FactsGetting facts right instead of making them up40Gemini 3.1 Pro4 of 4 tests
- Images and chartsUnderstanding pictures, charts and video20Gemini 3.1 Pro2 of 2 tests
- Following instructionsDoing exactly what it is asked20Gemini 3.1 Pro2 of 2 tests
- AgentsCarrying out multi-step tasks on its own21Gemini 3.1 Pro2 of 3 tests
- Long documentsFinding answers in very long texts10Gemini 3.1 Pro1 of 1 test
Long documents rests on a single test.
What it costs
Prices per million tokens, roughly 750,000 words. The bars show the cost of a million tokens read plus a million written.
GPT-5.1 costs 20% less for the same work.
The biggest differences
The tests each model wins by the widest margin, up to three each. Scores are out of 100.
Where Gemini 3.1 Pro pulls ahead
- Abstract visual puzzles that people can solveARC-AGI-2+59.5points ahead
- Finds hard-to-locate facts by browsing the webBrowseComp+35.1points ahead
- Common-sense trick questionsSimpleBench+26.4points ahead
Where GPT-5.1 pulls ahead
- Real work tasks from 44 professionsGDPVal+1.8points ahead
Every test, side by side
All 39 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingGemini 3.1 Pro
- Terminal-Bench 2.1Gemini 3.1 Pro by 21.473.852.4+21.4
- SciCodeGemini 3.1 Pro by 15.458.743.3+15.4
- Terminal-Bench HardGemini 3.1 Pro by 8.353.845.5+8.3
- LMArena · WebDevGemini 3.1 Pro by 52 rating points14471395+52 rating
- LiveCodeBench v6Gemini 3.1 Pro by 4.791.787+4.7
- SWE-bench VerifiedGemini 3.1 Pro by 4.380.676.3+4.3
AgentsGemini 3.1 Pro
- BrowseCompGemini 3.1 Pro by 35.185.950.8+35.1
- τ-Bench V3 · BankingGemini 3.1 Pro by 5.521.415.9+5.5
- GDPValGPT-5.1 by 1.814.716.5+1.8
ReasoningGemini 3.1 Pro
- ARC-AGI-2Gemini 3.1 Pro by 59.577.117.6+59.5
- SimpleBenchGemini 3.1 Pro by 26.479.653.2+26.4
- Humanity's Last ExamGemini 3.1 Pro by 18.54728.5+18.5
- CritPtGemini 3.1 Pro by 12.817.74.9+12.8
- GPQA DiamondGemini 3.1 Pro by 6.894.187.3+6.8
FactsGemini 3.1 Pro
- SimpleQA VerifiedGemini 3.1 Pro by 25.573.548+25.5
- AA-Omniscience · AccuracyGemini 3.1 Pro by 17.254.937.7+17.2
- Vectara HHEM hallucination ratelower is betterGemini 3.1 Pro by 1.710.412.1+1.7
- AA-Omniscience · Non-hallucinationGemini 3.1 Pro by 149.148.1+1
Images and chartsGemini 3.1 Pro
- MMMU-ProGemini 3.1 Pro by 6.982.475.5+6.9
- LMArena · VisionGemini 3.1 Pro by 46 rating points12961250+46 rating
Following instructionsGemini 3.1 Pro
- Multi-ChallengeGemini 3.1 Pro by 871.463.4+8
- IFBenchGemini 3.1 Pro by 4.277.172.9+4.2
Other results16 tests, not counted
Tests outside the eight areas. They are not counted above: several are summary scores built from other tests, or the same test under another name.
- AA-OmniscienceGemini 3.1 Pro by 26.531.95.4+26.5
- ARC-AGI-1Gemini 3.1 Pro by 25.29872.8+25.2
- Terminal-Bench 2.0Gemini 3.1 Pro by 20.968.547.6+20.9
- Artificial Analysis Coding IndexGemini 3.1 Pro by 19.468.849.4+19.4
- vectara_avg_summary_lengthGPT-5.1 by 146.7 rating points107.7254.4+146.7 rating
- τ²-Bench Telecom (AA run)Gemini 3.1 Pro by 13.795.681.9+13.7
- matharena_visual_math_overallGemini 3.1 Pro by 12.589.476.9+12.5
- AA Agentic IndexGPT-5.1 by 11.310.321.6+11.3
- HLE (with tools)Gemini 3.1 Pro by 8.751.442.7+8.7
- AA IntelligenceGemini 3.1 Pro by 529.724.7+5
- frontiermath_tier_4_v1Gemini 3.1 Pro by 4.216.712.5+4.2
- MMLU-ProGemini 3.1 Pro by 49187+4
- HMMT Nov. 2025Gemini 3.1 Pro by 3.194.891.7+3.1
- vectara_factual_consistencyGemini 3.1 Pro by 1.789.687.9+1.7
- MMMLUGemini 3.1 Pro by 1.692.691+1.6
- vectara_answer_ratetie99.4100tie
Questions people ask
Which is better, Gemini 3.1 Pro or GPT-5.1?
Gemini 3.1 Pro wins all seven areas where both have results: coding, agents, reasoning, facts, images and charts, long documents and following instructions. GPT-5.1 wins none, but costs 20% less.
Which is better for coding?
Gemini 3.1 Pro. It wins 6 of the 6 coding tests both models report; GPT-5.1 wins none.
Which is cheaper?
Gemini 3.1 Pro costs $2.00 per million input tokens and $12.00 per million output tokens; GPT-5.1 costs $1.25 and $10.00. That makes GPT-5.1 about 20% cheaper for the same work.
How do you compare the two?
We use the 39 benchmark tests both models have published scores on. The verdict counts the 23 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 16 are listed but not counted, because several are summary scores or repeat a test. Each score is the one shown on the model's own page.